Evaluating the co-use of opioids and cannabis for pain among current users using hypothetical purchase tasks

Background: Cannabinoids may potentiate opioid analgesia and therefore could be used to reduce reliance on opioids for analgesia. Aims: The current study evaluated whether the concurrent availability of cannabis influences opioid consumption using a behavioral economic demand framework. Methods: An online survey assessed cannabis and opioid use frequency and dependence measures, pain severity, and demand for both cannabis and opioids alone and when concurrently available using hypothetical purchase tasks. Adults reporting current use of opioids for pain management and past 30-day cannabis exposure (N=155) completed two hypothetical purchase tasks in which only grams of cannabis or units of participants' index opioids were available for purchase, and two hypothetical tasks in which both were concurrently available and the price of one drug increased whereas the other was kept constant. Paired-sample t-tests compared the demand of each drug alone with when it was available concurrently with an alternative. Results: Demand intensity was significantly reduced and demand elasticity was significantly increased for both cannabis and opioids when the alternate commodity was available, although the reductions in cannabis consumption were more pronounced than they were for opioid consumption in the presence of the alternate commodity. Conclusions: These data provide behavioral economic evidence that cannabis access may modestly reduce demand for opioids in persons who have pain. Additional clinical studies that evaluate the analgesic effects of cannabis and cannabis-opioid effects on pain are warranted.